cron sessions opening hundreds of times

linuxfia · 01-09-2009, 06:54 PM

Is it normal for the cron sessions to be opened hundreds of times per day?
I get this almost daily.

Quote:

cron:
Sessions Opened:
root: 345 Time(s)

Quote:

Jan 4 10:05:01 srv CRON[11065]: pam_unix(cron:session): session opened for us
er root by (uid=0)
Jan 4 10:05:03 srv CRON[11065]: pam_unix(cron:session): session closed for us
er root
Jan 4 10:09:01 srv CRON[11130]: pam_unix(cron:session): session opened for us
er root by (uid=0)
Jan 4 10:09:01 srv CRON[11130]: pam_unix(cron:session): session closed for us
er root
Jan 4 10:10:01 srv CRON[11139]: pam_unix(cron:session): session opened for us
er root by (uid=0)
Jan 4 10:10:04 srv CRON[11139]: pam_unix(cron:session): session closed for us
er root
Jan 4 10:15:01 srv CRON[11204]: pam_unix(cron:session): session opened for us
er root by (uid=0)
Jan 4 10:15:04 srv CRON[11204]: pam_unix(cron:session): session closed for us
er root
Jan 4 10:17:01 srv CRON[11269]: pam_unix(cron:session): session opened for us
er root by (uid=0)
Jan 4 10:17:01 srv CRON[11269]: pam_unix(cron:session): session closed for us
er root
Jan 4 10:20:01 srv CRON[11272]: pam_unix(cron:session): session opened for us
er root by (uid=0)
Jan 4 10:20:03 srv CRON[11272]: pam_unix(cron:session): session closed for us

repo · 01-10-2009, 02:52 AM

take a look at the cronjobs that are installed.

linuxfia · 01-12-2009, 11:10 AM

There's only root cron and none of the jobs are set to launch every minute...

chrism01 · 01-12-2009, 07:33 PM

You need to examine closely what those cron jobs are actually doing. Could be looping, could be retrying something.
Those msgs say that a prog that is running as the cron user is trying to connect/login/switch user frequently.

BinWondrin · 01-12-2009, 09:43 PM

Other than other UNIX systems, Linux has a whole array of cron directories in which cron jobs can be placed.
So, if you issue to list cronjobs

Code:

crontab -l

you will only see whatever was created with

Code:

crontab -e

If you check the contents of the following directories:

Code:

cron.d/
cron.monthly/ 
cron.weekly/  
cron.daily/
cron.hourly/

you will find other re-defined cron jobs such as log rotate etc.

This might be where you can find your mysterious cron jobs.

Hope this helps.
:-)

BW

linuxfia · 01-14-2009, 06:24 PM

Thanks.
I checked all the crons (var/spool/cron/crontab/) and in the /etc/cron... directories and it's hard to find out which cron is causing this. The log doesn't say which cron so it's difficult to pinpoint.